First let me start by saying I know just enough to be dangerous. This spring I changed the oil in my John Deere mower with a 15hp Kohler engine. There was a lot of gas in the oil, so I ordered a carburetor rebuild kit. Cleaned and rebuilt the carb. Started and cut the lawn for about 20 minutes then it started blowing blue smoke. Checked the oil and there was gas in it. How is gas getting into the crank case while the engine is running? Can it get in via the fuel pump? Thanks in advance for all of your help!
Gas in my oil
- Thread starter divemark
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If the fuel pump diaphragm has a hole in it, darned right gas can get into the oil.
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ie a stuck float
Originally Posted By: Rand
everytime I've had that problem it was leaking past the carb when it was off.
a manual fuel switch is cheap fix.
if you check the oil level before you might not notice the gas on the dipstick because it will be on top and clear.
Originally Posted By: Rand
everytime I've had that problem it was leaking past the carb when it was off.
a manual fuel switch is cheap fix.
if you check the oil level before you might not notice the gas on the dipstick because it will be on top and clear.
one of my line painting machines had so much had in it the piston would not go down. Just drained it out and out new oil in and good to go. The problem on mine was a piece of dirt got stuck in the needle which drained the whole tank into the oil.
I have a Murphy riding mower and after several "fixes", I finally put a fuel shut-off valve in the gas tank to carb line. Just must remember to turn if off promptly when shutting off the engine. Ed
I have a shutoff valve on most of my equipment. I close the valve while the engine is still running to drain down the carb bowl. The next time you open the valve, the needle and seat get a quick flush as the bowl refills.
Originally Posted By: divemark
First let me start by saying I know just enough to be dangerous. This spring I changed the oil in my John Deere mower with a 15hp Kohler engine. There was a lot of gas in the oil, so I ordered a carburetor rebuild kit. Cleaned and rebuilt the carb. Started and cut the lawn for about 20 minutes then it started blowing blue smoke. Checked the oil and there was gas in it. How is gas getting into the crank case while the engine is running? Can it get in via the fuel pump? Thanks in advance for all of your help!
Assuming it ran as expected till the smoking started, I doubt the carb is at fault... If it has a diaphragm F/P that's bolted directly to and operated by the engine, it'd be my current suspect...
First let me start by saying I know just enough to be dangerous. This spring I changed the oil in my John Deere mower with a 15hp Kohler engine. There was a lot of gas in the oil, so I ordered a carburetor rebuild kit. Cleaned and rebuilt the carb. Started and cut the lawn for about 20 minutes then it started blowing blue smoke. Checked the oil and there was gas in it. How is gas getting into the crank case while the engine is running? Can it get in via the fuel pump? Thanks in advance for all of your help!
Assuming it ran as expected till the smoking started, I doubt the carb is at fault... If it has a diaphragm F/P that's bolted directly to and operated by the engine, it'd be my current suspect...
as everyone else said the best cheapest fix is a little plastic shut off valve on the fuel line and you will be good to go.
Originally Posted By: AandPDan
A shut off won't help. It's the fuel pump. He says it happened while running.
If it was leaking via the float then the engine would running very rich and flooding out, if it ran at all.
Bad diaphragm on the pump. It happens.
+1
A shut off won't help. It's the fuel pump. He says it happened while running.
If it was leaking via the float then the engine would running very rich and flooding out, if it ran at all.
Bad diaphragm on the pump. It happens.
+1
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